How to pull up the selected edge and scale to the center at the same time?
I stand corrected on my comment, the 'Normal' orientation is not needed here, (although the combination of 'Individual Origins' and the 'Normal' orientation is very handy in situations like this.)
With Pivot set to 'Individual Origins', amd Orientation left at 'Global':
Having Alt selected the horizontal edge loops, and used CtrlShiftNumpad + from initial pairs to select every other cut between tiles, they are V ripped to separate the faces.
Then in Face mode, all faces are S scaled down a bit to make selection of tile bottom-edges a bit easier. With that Edge mode selection, and the cursor near the middle of the view...

GZ raise the bottom edges to tilt the tiles without splaying their bottom corners, and then GG slide, with Alt held to release the clamp.
The tiles can be scaled back again if you want to reduce the cracks between them. Various tile-bottoms are moved up and down a bit, using GG again, for a chirpy randomness. Maybe CtrlShiftB bevelling the corner-vertices makes the tiles a bit cuter.
After Solidify, Bevel (by angle) and Subdivision Surface modifiers..